My old boss said to stop using wire nuts on alarm panels and I ignored him for 2 years
Back when I started doing installs in 2019, my lead guy Dave kept telling me to use crimp connectors on panel wiring instead of wire nuts. He said vibration and heat in the can would loosen them over time. I nodded and kept twisting wire nuts on because they were faster and I had a bucket of 500 of them. Fast forward to last month, I got called back to a house in Mesa where the panel kept throwing a zone fault. Opened it up and found 4 wire nuts had backed off just enough to make intermittent contact. Spent 3 hours chasing a ghost when the fix took 90 seconds with a crimper. Dave retired in 2021 but I still hear his voice every time I reach for a wire nut. Now I want to know if anyone else has a hill they died on that a mentor called years earlier. What is the one tip you ignored that came back to bite you?
Ran into the same thing on a panel in a garage that got full afternoon sun. Those wire nuts would loosen up every summer from the heat cycling and I'd get called back for random trouble signals. Switched to crimp sleeves with a good ratcheting crimper and never had a callback on one of those panels again. The trick is you gotta use the right size sleeve for the wire gauge and give it a solid tug after to make sure it's tight. Dave was right, vibration and heat will walk a wire nut loose every time, it's just slow enough that you don't notice until it bites you.